Jack Crosbie

Patterns of spinal motion during walking

We present the results of a study in which we investigated the patterns of movement of the lower thoracic and lumbar spinal segments and the pelvis in subjects walking at a self-selected speed. Our subjects were 108 healthy adults aged from 20 to 82 years and were equally divided with respect to gender. Measurements were carried out using a video-based system by which the trunk was partitioned into segments and the movements of these segments about three orthogonal axes recorded. We found consistent patterns within and between segments and movements, with apparent consequential trunk motion following pelvic displacements. This suggests that the spinal movements associated with walking are linked to the primary motions of the pelvis and the lower limbs.

Effect of low back pain on the kinematics and joint coordination of the lumbar spine and hip during sit-to-stand and stand-to-sit

Study Design. Experimental study to describe lumbar spine and hip joint movements during sit-to-stand and stand-to-sit. Objectives. To examine differences in the kinematics and joint coordination of the lumbar spine and hips during sit-to-stand and stand-to-sit between healthy subjects and patients with subacute low back pain (LBP). Summary of Background Data. There is a paucity of information on the coordination of movements of lumbar spine and hips during sit-to-stand and stand-to-sit. The effect of LBP, with or without nerve root signs, is largely unknown. Methods. A three-dimensional real-time electromagnetic tracking device was used to measure movements of the lumbar spine and hips during sit-to-stand and stand-to-sit. Sixty subacute LBP participants with or without straight leg raise signs and 20 healthy asymptomatic participants were recruited. The kinematic patterns of lumbar spine and hips were analyzed. Coordination between the two joints was studied by relative phase angle analysis. Results. The mobility of the spine and hips was significantly limited in back pain subjects. It was observed that LBP subjects employed various strategies to compensate for the limited motions at the hips and lumbar spine. The contribution of the lumbar spine relative to that of the hip was found to be reduced for subjects with LBP. The lumbar spine-hip joint coordination was significantly altered in back pain subjects, in particular, those with positive straight leg raise sign. Conclusion. Back pain was related to changes in the kinematics and coordination of the lumbar spine and hips during sit-to-stand and stand-to-sit. Assessment of back pain patients should include kinematic analysis of the hips as well as the spine.

Does spasticity contribute to walking dysfunction after stroke

OBJECTIVES Clinically, it is assumed that spasticity of the calf muscles interferes with walking after stroke. The aim was to examine this assumption by evaluating the contribution of spasticity in the gastrocnemius muscle to walking dysfunction in an ambulant stroke population several months after stroke. METHODS Fourteen stroke patients who were able to walk independently and 15 neurologically normal control subjects were recruited. Both resting and action stretch reflexes of the gastrocnemius muscle were investigated under conditions that simulated walking. Resting tonic stretch reflexes were measured to assess spasticity whereas action tonic stretch reflexes were measured to assess the possible contribution of spasticity to gait dysfunction. RESULTS Two thirds of the stroke patients exhibited resting tonic stretch reflexes which indicate spasticity, whereas none of the control subjects did. However, the stroke patients exhibited action tonic stretch reflexes that were of similar magnitude to the control subjects, suggesting that their reflex activity during walking was not different from that of control subjects. Furthermore, there was no evidence that the action stretch reflex in the stroke patients contributed a higher resistance to stretch than the control subjects. CONCLUSIONS Whereas most of the stroke patients exhibited spasticity when measured both clinically and physiologically, they did not exhibit an increase in resistance to dorsiflexion due to exaggerated action tonic stretch reflexes. It is concluded that it is unlikely that spasticity causes problems in walking after stroke in ambulant patients. Therefore, it seems inappropriate to routinely reduce or inhibit the reflex response to improve functional movement in stroke rehabilitation. Factors other than spasticity should be considered when analysing walking after stroke, so that appropriate treatment is provided to patients.

Age, gender and speed effects on spinal kinematics during walking

We present the results of a study in which we investigated the patterns and ranges of movement of the lower thoracic and lumbar spinal segments and the pelvis in subjects walking at two self-selected speeds. Our subjects were aged from 20 to 82 years and both genders were equally represented. Measurements were carried out using a video-based system. We detected increased range of motion in each segment with increased walking speed, few gender-related differences in patterns or ranges of motion and significant reduction in spinal range of motion with advancing age. Our findings suggest, however, that these age-related changes are more likely to be step-length dependent than an intrinsic feature of aging.

Effective orthotic therapy for the painful cavus foot : a randomized controlled trial

Patients with a cavus or high-arched foot frequently experience foot pain, which can lead to significant limitation in function. Custom foot orthoses are widely prescribed to treat cavus foot pain. However, no clear guidelines for their construction exist, and there is limited evidence of their efficacy. In a randomized, single-blind, sham-controlled trial, the effect of custom foot orthoses on foot pain, function, quality of life, and plantar pressure loading in people with a cavus foot type was investigated. One hundred fifty-four participants with chronic musculoskeletal foot pain and bilateral cavus feet were randomly assigned to a treatment group receiving custom foot orthoses (n = 75) or to a control group receiving simple sham insoles (n = 79). At 3 months, 99% of the participants provided follow-up data using the Foot Health Status Questionnaire. Foot pain scores improved more with custom foot orthoses than with the control (difference, 8.3 points; 95% confidence interval [CI], 1.2 to 15.3 points; P = .022). Function scores also improved more with custom foot orthoses than with the control (difference, 9.5 points; 95% CI, 2.9 to 16.1 points; P = .005). Quality-of-life data favored custom foot orthoses, although differences reached statistical significance only for physical functioning (difference, 7.0 points; 95% CI, 1.9 to 12.1 points; P = .008). Plantar pressure improved considerably more with custom foot orthoses than with the control for all regions of the foot (difference, ‐3.0 N . s/cm 2 ; 95% CI, ‐3.7 to ‐2.4 N . s/cm 2 ; P < .001). In conclusion, custom foot orthoses are more effective than a control for the treatment of cavus foot pain and its associated limitation in function. (J Am Podiatr Med Assoc 96(3): 205-211, 2006)

Normative data for passive ankle plantarflexion–dorsiflexion flexibility

OBJECTIVE To describe the normal distribution parameters for measures of passive ankle plantarflexion-dorsiflexion flexibility obtained from a large sample of able-bodied young adult subjects. DESIGN Seven variables were assessed and descriptive analyses were conducted. BACKGROUND While assessment of plantarflexion-dorsiflexion flexibility is an important component of a clinical examination of plantarflexion contracture, there is limited normative data available that can be used as a reference for clinical decision-making. METHODS Data were collected from 300 able-bodied male and female subjects aged between 15 and 34 years. Both ankles were measured. Load-displacement curves were collected using a manually controlled instrumented footplate. Six variables were extracted from these curves: passive torque at zero and 10 deg, passive stiffness at zero and 10 deg, and two coefficients from an equation fitted to the curve (i.e., k and b). The seventh variable, passive dorsiflexion range of motion, was quantified using a clinical procedure. RESULTS Flexibility variables did not differ between the left and right ankles, nor between the dominant and non-dominant legs. All variables were normally distributed. These distributions can, therefore, be adequately described using their mean and standard deviation values. CONCLUSIONS This study has substantially increased the available database on plantarflexion-dorsiflexion flexibility and forms the basis of norm-referenced clinical tests.

Movement coordination of the lumbar spine and hip during a picking up activity in low back pain subjects

The effect of low back pain, with or without nerve root signs, on the joint coordination and kinematics of the lumbar spine and hips during everyday activities, such as picking up an object from the floor, are largely unknown. An experimental study was designed to compare lumbar spine and hip joint kinematics and coordination in subjects with and without sub-acute low back pain, while picking up an object in a sitting position. A three-dimensional real-time electromagnetic tracking device was used to measure movements of the lumbar spine and hips. Sixty participants with subacute low back pain, with or without straight leg raise signs, and twenty healthy asymptomatic participants were recruited. The ranges of motions of lumbar spine and hips were determined. Movement coordination between the two regions was examined by cross-correlation. Results showed that mobility was significantly reduced in subjects with back pain, who compensated for limited motion through various strategies. The contribution of the lumbar spine relative to that of the hip was, however, found to be similar in all groups. The lumbar spine–hip joint coordination was substantially altered in subjects with back pain, in particular, those with a positive straight leg raise sign. We conclude that changes in the lumbar and hip kinematics were related to back pain and limitation in straight leg raise. Lumbar–hip coordination was mainly affected by the presence of positive straight leg raise sign when picking up an object in a sitting position.

Three-dimensional kinetics of the lumbar spine and hips in low back pain patients during sit-to-stand and stand-to-sit

Study Design. Experimental, biomechanical study to determine the kinetics of the lumbar spine and hips during sit-to-stand and stand-to-sit. Objective. To investigate the effects of back pain, with and without limitation in straight leg raise, on the joint moment and power of the lumbar and hips during sit-to-stand and stand-to-sit. Summary of Background Data. Movements of the lumbar spine and hips, and their coordination have been reported to be affected by the presence of low back pain (LBP), especially in those with a positive straight leg raise. However, the literature has no information concerning moment and power characteristics of the lumbar spine and hips during sit-to-stand and stand-to-sit in such patients. Methods. Twenty asymptomatic subjects, 20 LBP patients, and 20 patients with LBP and a positive straight leg raise sign were requested to perform the sit-to-stand and stand-to-sit activities. Electromagnetic sensors were attached to the body segments to measure their kinematics while 2 nonconductive force plates gathered ground reaction force data. Biomechanical models were used to determine the muscle moments and power at the lumbosacral (L5/S1) joint and hips. Results. Muscle moments acting at the lumbar spine and hip in the sagittal plane were found to decrease in subjects with LBP, but there were significant increases in moments in other planes of motion. The power patterns of the spine and hips were also significantly altered, particularly in subjects with a positive straight leg raise sign. Conclusions. Back pain subjects exhibit compensatory movements and altered load sharing strategies during the sit-to-stand and stand-to-sit activities. Exercise therapy should take account of these changes so that the normal kinematic and kinetic characteristics of the spine and hips can be restored.

Benefits of FES gait in a spinal cord injured population.

Study design:Review.Objectives:This review article investigated the objective evidence of benefits derived from functional electrical stimulation (FES)-assisted gait for people with spinal cord injury (SCI). Both FES and gait have been proposed to promote not only augmented health and fitness, but specific ambulatory outcomes for individuals with neurological disabilities. However, due to small sample sizes and the lack of functionality of the intervention, it has not been widely used in clinical practice. This review assessed whether there is sufficient evidence to encourage a more widespread deployment of FES gait within the rehabilitation community.Methods:Hand searches and online data collection were performed in Medline and Science Direct. Specific search terms used included SCI/paralysis/paraplegia and tetraplegia with electrical stimulation/FES, gait and walking.Results:The searches generated 532 papers. Of these papers, 496 were excluded and 36 papers were included in the review. Many reported benefits were not carefully investigated, and small sample sizes or different methodologies resulted in insufficient evidence to draw definitive conclusions.Conclusions:FES gait can enhance gait, muscle strength and cardiorespiratory fitness for people with SCI. However, these benefits are dependent on the nature of the injury and further research is required to generalize these results to the widespread population of SCI individuals. Proof of the functionality and further evidence of the benefits of FES gait will assist in FES gait gaining clinical acceptance.

Symptomatic and asymptomatic movement coordination of the lumbar spine and hip during an everyday activity

Study Design. This experimental study analyzed the movements of the lumbar spine and hip while putting on a sock. Objectives. To examine differences in kinematics and coordination of the lumbar and hip movements in subjects with and without subacute low back pain. Summary of Background Data. There is no information on the coordination of movements of lumbar spine and hips during activities of daily living such as putting on a sock. The effect of low back pain, with or without nerve root signs, is unknown. Methods. A real-time three-dimensional electromagnetic tracking device was used to measure movements of the lumbar spine and hips in 60 subacute low back pain subjects with or without straight leg raise (SLR) signs and 20 asymptomatic subjects. Movement coordination between the two regions was examined by cross-correlation. Results. Mobility was significantly reduced in back pain subjects. Symptomatic subjects compensated for limited motion through various strategies, but in all cases the contribution of the lumbar spine relative to that of the hip was significantly reduced. The lumbar spine-hip joint coordination was substantially altered in back pain subjects, in particular, when putting on a sock on the side with positive SLR sign. Conclusion. Changes in the lumbar and hip kinematics when putting on a sock were related to back pain and limitation in SLR. Low back pain will affect lumbar-hip coordination.